@article{journal,
author = {Lurz, P. W. W. and Shirley, M. D. F. and Geddes, N.},
title = {Monitoring low density populations: a perspective on what level of population decline we can truly detect},
year = {2008},
volume = {31.1},
pages = {29--39},
journal = {Animal Biodiversity and Conservation},
keywords = {Ardilla, Sciurus vulgaris, Conservaci{\'o}n, An{\'a}lisis de potencia}
}